This proposal is aimed at the preparation and application of novel advanced bead polymers for use as packing materials in the high performance liquid chromatography of organic and biological fluids. The new monosized polymer beads would complement, and in some cases replace, existing silica-based materials by providing increased chemical stability as well as added functionality and versatility. In particular, new approaches to polymer beads that can perform several analyses in a single column are sought. These unprecedented truly "multimodal" chromatographic media would be able to separate several classes of compounds such as proteins, drugs, and metabolites in a single column through a simple change in eluting solvent between each mode of chromato- graphic separation. To achieve this goal, important targets include the control of porous structures of the uniformly sized polymer beads, the control of the chemistry at the surface of their pores through a site selective separation process or a pore size-selective modification technique. For example, a bimodal column for the direct analysis of blood plasma might contain large hydrophilic pores for the analysis of proteins by aqueous size-exclusion chromatography, and small hydrophobic pores for the analysis of drugs and metabolites by reversed-phase chromatography. Several other types of bimodal as well as trimodal columns will be designed and prepared. The advantages of these multimodal columns are numerous: they facilitate analysis by eliminating steps of sample preparation or precolumn treatment, they provide a complete view of the contents of the biological fluid rather than a restricted view of one type of component only, and they reduce the complexity of instrumentation needed for the analysis. Similarly, great versatility is achieved as a vast array of monomers with reactive groups useful for advanced separations will be introduced in the new bead materials. In addition to direct applications to the analysis of biological and organic solutions, the new media can find applications in classical high performance liquid chromatography as they are extremely rugged and can operate in a broad spectrum of solvents over the entire pH range. Finally, tests on artificial samples will be carried out to evaluate their applicability to the determination of trace amounts of materials such as N-acetylneuraminic acid (for cancer diagnosis) or hemoperfusion. This study will also provide a fundamental understanding of the requirements for optimal porous particulate separation media for use in the analysis of biological samples.